revealing that you are a letter of Christ, delivered by us, written not with ink but by the Spirit of the living God, not on stone tablets but on tablets of human hearts.

not to be easily shaken from your composure or disturbed by any kind of spirit or message or letter allegedly from us, to the effect that the day of the Lord is already here.

speaking of these things in all his letters. Some things in these letters are hard to understand, things the ignorant and unstable twist to their own destruction, as they also do to the rest of the scriptures.